Wordpress: Display posts by custom select query - wordpress

Question

I need to get posts by custom category id, sort by custom field value and with another custom field if this field exists. I think I need to use custom selection query. Look at my query: The problem is that this query returns the same post 5 times... In admin panel I made 20 posts per page. Maybe someone have their own solution ? Thanks.
$wp_query->request = "SELECT * FROM $wpdb->posts
LEFT JOIN $wpdb->postmeta ON($wpdb->posts.ID = $wpdb->postmeta.post_id)
LEFT JOIN $wpdb->term_relationships ON($wpdb->posts.ID = $wpdb->term_relationships.object_id)
LEFT JOIN $wpdb->term_taxonomy ON($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id)
LEFT JOIN $wpdb->terms ON($wpdb->terms.term_id = $wpdb->term_taxonomy.term_id)
WHERE $wpdb->terms.slug = 'categoryname'
AND $wpdb->term_taxonomy.taxonomy = 'category'
AND $wpdb->posts.post_status = 'publish'
AND $wpdb->posts.post_type = 'post'
ORDER BY $wpdb->posts.post_date DESC";
$pageposts = $wpdb->get_results($wp_query->request, OBJECT);

Answer 1

$customSelect = new WP_Query(array(
'post_type' => 'post',
'posts_per_page' => 10,
'taxonomy' => 'category',
'order' => 'DESC',
'meta_key' => 'your custom field',
'orderby' => 'meta_value'
This is probably way off what your trying to achieve, the only bit I can't get my head round is how to test if meta key exists using a variable or something.
Anyways good luck

Answer 2

Why you use "$wp_query->request", this variable is for retrieving last query result, not to set new one...
just try
$my_custom_sql = "SELECT * FROM $wpdb->posts
LEFT JOIN $wpdb->postmeta ON($wpdb->posts.ID = $wpdb->postmeta.post_id)
LEFT JOIN $wpdb->term_relationships ON($wpdb->posts.ID = $wpdb->term_relationships.object_id)
LEFT JOIN $wpdb->term_taxonomy ON($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id)
LEFT JOIN $wpdb->terms ON($wpdb->terms.term_id = $wpdb->term_taxonomy.term_id)
WHERE $wpdb->terms.slug = 'categoryname'
AND $wpdb->term_taxonomy.taxonomy = 'category'
AND $wpdb->posts.post_status = 'publish'
AND $wpdb->posts.post_type = 'post'
ORDER BY $wpdb->posts.post_date DESC";
$pageposts = $wpdb->get_results($my_custom_sql, OBJECT);

Answer 3

Try this-
get_results(
"
SELECT * FROM $wpdb->posts
LEFT JOIN $wpdb->term_relationships ON
($wpdb->posts.ID = $wpdb->term_relationships.object_id)
LEFT JOIN $wpdb->term_taxonomy ON
($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id)
WHERE $wpdb->posts.post_status = 'publish'
AND $wpdb->term_taxonomy.taxonomy = 'category'
AND $wpdb->term_taxonomy.term_id = 3
ORDER BY post_date ASC
"
); ?>